Just for those who don't know: If you install both Divx AND 3ivx, you get Divx audio handling + 3ivx's superior video handling. Note that some people have reported that the lastest version of Divx always tries to handle the video, overriding 3ivx, however I've never had this problem. YMMV.
As for the original question...sorry, beats me. If there haven't been any stability problems, I'd just grin and bear it until the Divx folks release an update. Of course, you might want to drop them an email letting them know of the issue.
It does seem like an awfully strange problem, though. Especially since QuickTime Player 6 doesn't even have one help menu, so it's hard to imagine Divx is trying to do anything with it at all. But again, I wouldn't worry about it unless things get unstable.